The present invention relates to an improved buoyant pyrotechnic marine marker, deployable from an aircraft, of the type comprising a water impermeable jacket enclosing a pyrotechnic candle, ignition means for the candle consisting of a salt and/or fresh water actuable battery, a candle-igniting squib electrically acutated by the battery and circuitry means extending between the battery and the squib. The jacket has aperture means to be positioned below the water level when the marker is deployed in water to permit water to enter the jacket to actuate the battery. Arming means are mechanically associated with the jacket, and normally close the aperture means but are manipulable to open the aperture means as required. The jacket has a gas emission hole for escape of the combustion gases produced by the candle when ignited.
Such marine markers of conventional construction have presented a number of problems in their usage. These problems are with respect to arming and firing, wastage, ease of use and safety. For example, the arming and firing mechanism for the currently used marker has been thought to result in misfires. The device conventionally has a water activated battery actuated in a chamber, and, in use, air can become trapped in that chamber preventing water from coming in contact with the battery. Additionally, activation of the present water involves two operations: rotation of a cover and opening of two water intake ports to the chamber. Users are often forced to use makeshift tools in order to turn that cover because there is too much friction between the moving parts. Because the activation operations are often difficult to perform, for the sake of efficiency a user will often prepare three, four or five smoke markers in advance for dropping from the aircraft as soon as a locating mission is ordered. In most cases, not all the markers prepared are used. Since the arming mechanisms on them, when armed, are not reversible, it is impossible to turn them back to the safe (unarmed) position. Thus users often throw them into the sea simply to get rid of them.
Another problem with the current marker used is that in the safe, unarmed position, the electrical circuitry which extends between the battery and the firing squib is always closed. There is no switch to open that circuit. This means that, even in the unarmed position, the activating medium (salt and/or fresh water) may accidentally reach the battery and quickly trigger the marker. This is of concern to users since, if they had to make an emergency landing on water and damaged markers were exposed to water, they might become triggered resulting in a major fire and potential fatalities to the crew from the smoke and flame generated by the markers.
Another problem experienced with current marker devices is that they cannot withstand severe temperature and humiditiy conditions. The chamber within which the battery is contained has poor water tightness. This defect usually does not risk accidently activating the smoke marker since, in these cases, the reaction is so slow that the battery does not provide the power required to ignite the squib. Nevertheless, the slow deterioration thereby caused to the battery may cause such smoke markers to become unreliable or unusable.
It is an object of the present invention to provide an improved buoyant pyrotechnic marine marker which avoids or reduces some of these problems with conventional marker devices.